Structural models for calculating shear force in columns due to masonry-frame interaction in concrete building under seismic loads

Abstract

This paper presents a comparative study of the different structural models for obtaining the additional shear force in reinforced concrete columns, due to the masonry structure interaction under seismic loads, for design applications. Simplified models, as in those that use a single equivalent diagonal strut and multiple equivalent diagonal struts, for the simulation of masonry wall infill, were employed. The efficiency of such models was evaluated based on two- and three-dimensional modelling via the Finite Element Method, through simulating the contact problem between masonry infill and the concrete frame. These comparisons are centered on examples of single-story and multiple-story masonry infilled frames. The results obtained confirm that the classic concentric strut model significantly underestimates the values of the maximum shear forces in the columns and that such values can be better predicted when adaptations are made to the model for the transfer of the axial force on the equivalent diagonal strut along the contact length of the column and the wall.